The present invention relates to a method and apparatus for melt spinning, and more particularly, to a method and apparatus for melt spinning which is effective in the spinning of pitch carbon fibers.
In melt spinning, particularly high-temperature melt spinning, such as the spinning of pitch carbon fibers, a volatile low-molecular gas, e.g., oil smoke (of the heavy hydrocarbon component) is generated from the spinneret and the spun filaments to cause "wetting", that is, the generated volatile low-molecular gas adheres to the surfaces of the spinneret plate and various members in the vicinity of the spinneret plate, such as the heating tube, and contaminates the spinneret plate, the heating tube, etc. This wetting results in oscillation of the spun filaments, causing fusion of the spun filaments or unevennesses in denier, or even the breakage of the filaments in the worst case, which makes it impossible to effect stable spinning over a long period of time.
In order to prevent this wettin in melt spinning, methods have hitherto been proposed such as sucking away the gases in the vicinity of the spinneret plate, or forcibly blowing cooling gas onto the surface of the spinneret plate. It has, however, been found that stable spinning cannot be effected by these conventional methods in high-temperature melt spinning, such as the spinning of pitch carbon fiber.